WO1996018096A1 - Detection quantitative d'especes chimiques - Google Patents

Detection quantitative d'especes chimiques Download PDF

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Publication number
WO1996018096A1
WO1996018096A1 PCT/GB1995/002862 GB9502862W WO9618096A1 WO 1996018096 A1 WO1996018096 A1 WO 1996018096A1 GB 9502862 W GB9502862 W GB 9502862W WO 9618096 A1 WO9618096 A1 WO 9618096A1
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WO
WIPO (PCT)
Prior art keywords
sample
species
concentration
absorbance
target
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/GB1995/002862
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English (en)
Inventor
Mark Johnson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
North West Water Group PLC
United Utilities PLC
Original Assignee
North West Water Group PLC
United Utilities PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GBGB9424922.4A external-priority patent/GB9424922D0/en
Priority claimed from GBGB9502683.7A external-priority patent/GB9502683D0/en
Application filed by North West Water Group PLC, United Utilities PLC filed Critical North West Water Group PLC
Priority to AU41209/96A priority Critical patent/AU4120996A/en
Priority to GB9711721A priority patent/GB2310717B/en
Publication of WO1996018096A1 publication Critical patent/WO1996018096A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
    • G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
    • G01N21/631—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited using photolysis and investigating photolysed fragments
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/1717—Systems in which incident light is modified in accordance with the properties of the material investigated with a modulation of one or more physical properties of the sample during the optical investigation, e.g. electro-reflectance
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/33—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using ultraviolet light
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/75—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated

Definitions

  • This invention relates to a method and apparatus for the quantitative detection of chemical species.
  • Chlorine disinfection is most commonly effected using gaseous chlorine or sodium h pochlorite. Both methods of disinfection initially produce hypochlorous acid (HOC1) which then dissociates to OC1 " and H + ions.
  • HOC1 hypochlorous acid
  • the concentration of each ion is a function of the pH and temperature of the solution, and probably also of the water's background history and other chemical constituents.
  • the presence of two species of disinfectants of different strengths is the main difficulty in chlorine disinfectant measurement, and ideally each species should be measured independently.
  • UV spectroscopy measures the transmission of a beam of light through a parallel-sided cell containing the sample. A fraction of the light is absorbed by the sample, with each species in the sample absorbing light at a characteristic wavelength.
  • the absorption curves of HOC1 and OCI " show strong absorption features at about 23Snm and 292nm.
  • the sample may contain other species with characteristic absorption peaks, for example, chloramines (added deliberately to the water in some circumstances to provide a long-lasting disinfectant residual) at 254nm, SO 2 , 0 3 , and aluminium-and ferric-based coagulants.
  • particles present in the water such as colloids and bubbles, etc, give rise to a featureless apparent-absorption spectrum which causes severe baseline shifts in all spectra, making true absorption measurements more difficult.
  • British Patent No. 1570236 describes a method for detecting the presence in a sample of photochemicall modifiable constituents such as cannabinoids, the method relying upon high pressure liquid chromatography.
  • HPLC is capable of very effectively separating a target constituent such as cannabinoid from the other constituents of a complex mixture. This is the source of the technique's high selectivity.
  • the separated constituent may be difficult to detect.
  • cannabinoid is invisible (because of inconveniently low optical absorption) to a single-wavelength photometric detector.
  • the target constituent is modified photochemically by irradiation with light.
  • the photochemical modification may convert the target constituent to a species having different fluorescent characteristics, or different light absorbance at a particular wavelength.
  • Selectivity may be increased by comparing measurements of florescence, intensity or absorbance strength taken from modified and unmodified samples. Data to be compared can be generated either by temporarily discontinuing the photochemical modification of the eluent stream passing through a single detector, or by passing a stream through two detectors arranged in series and photochemically modifying the stream at a point between the two detectors.
  • a method for determining the concentration of a target chemical species in a sample wherein the absorbance of the sample is measured across a range of wavelengths to produce a first absorbance spectrum, the sample is exposed to conditions which modify the concentration of the target chemical species in the sample, the absorbance of the sample is re-measured across the said range of wavelengths to produce a second absorbance spectrum, and differences between the two spectra are analysed to quantify the concentration of the target chemical species in the unmodified sample.
  • the concentration of the target chemical species, and hence the optical spectrum may be modified by photolysis, by photolysis in combination with a photoconductor (e.g. TiO 2 ) capable of generating highly reactive species such as OH radicals, or by injecting similar reactive species into the sample from a high voltage corona.
  • a photoconductor e.g. TiO 2
  • these techniques may be combined to produce a set of modified spectra which together unambiguously characterise the target species.
  • the present invention is based on the realisation that it is possible to highly selectively quantify the concentration of target chemical species through analysis of small absorbance changes effected by modification of the target's absorbance spectrum.
  • the use of full spectral information, combined with chemical modification of the target, provides a double ''signature" characteristic of the target species.
  • the target species is modified without any other constituent of the sample being modified.
  • the sample may be photolytically modified by exposing it to UV or visible light generated by a continuously or intermittently operating light source.
  • a corona discharge may be generated by applying a voltage between a first electrode spaced from the sample and a second electrode immersed in the sample.
  • a grounded electrode may be positioned between the first electrode and the sample to remove charged species.
  • the invention also provides an apparatus for determining the concentration of a target chemical species in a sample, comprising a spectrometer for making successive measurements of the absorbance of the sample across a range of wavelengths to produce at least two absorbance spectra, means for exposing the sample to conditions which modify the concentration of the target species in the sample, and means for comparing spectra generated before and after exposure of the sample to quantify the concentration of the target species.
  • Figs. 1 and 2 show absorbance spectra for two samples, modifications to the spectra resulting from photolysis, and the difference between the modified and unmodified spectra;
  • Fig. 3 shows conventional spectra of some common disinfectant species and tap water
  • Fig. 4 shows reduction of the OCI ' absorption peak following irradiation with a low-pressure mercury lamp
  • Fig. 5 shows the spectral modulation due to a series of flashes from a xenon flash lamp for an acidic solution of chlorine (mostly HOC1 species present);
  • Fig. 6 shows the difference spectra according to the present invention for a single concentration of chlorine at different pH values and for a tap water sample
  • Fig. 7 shows the difference spectra in alkaline conditions for a series of chlorine concentrations from 0.75 ppm to 16 ppm.
  • Fig. 8 is a sectional side view of a corona discharge cell used in accordance with an embodiment of the present invention.
  • Fig. 9 is a section through Fig. 8 on line 9-9;
  • Fig. 10 illustrates the change in absorbance at various wavelengths with a hypochlorite-containing water sample with successive corona irradiations
  • Fig. 11 illustrates absorbance versus wavelength for a sample containing methylene blue with successive corona irradiations
  • Figs. 12 and 13 illustrate absorbance difference versus wavelength resulting from photolytic degradation for nine calibration samples.
  • Figs. 14 and 15 illustrate calibration data derived from the absorbance differences represented in Figures 10 and 11.
  • Fig. 1 shows in full line an absorbance spectrum including background effects generated from a water sample.
  • the broken line represents a spectrum taken from the same sample after a target species has been subjected to photolytic degradation.
  • a further full line represents the difference between the two spectra.
  • Fig. 2 shows equivalent curves for a water sample in which photolysis results in a more complex modification of the spectrum.
  • the present invention is based on the realisation that analysis of the ''difference" spectrum makes it possible to quantify the concentration in the sample of the species which is affected by photolysis.
  • Figs. 3 to 7 show the results of experiments to determine the feasibility of the method of determining the concentrations of chlorine disinfectant present in a sample of water according to the present invention.
  • the experiments were conducted using conventional UV spectroscopy equipment.
  • Light from a deuterium lamp was shone through the sample, which was placed in a 10mm path length UV-siiica cuvette.
  • the deuterium lamp typically produces a continuous, line-free spectrum in the range 160-360nm.
  • the emitted radiation density varies from a few mWcm ' nm sr " to a tenth of this over this range.
  • Typical lamps are operated at 80-100V at a current of 300mA after a heating and ignition phase. After the light has passed through the sample, it is detected across the range of wavelengths of light emitted by the lamp to obtain absorption spectra using a wavelength dispersing grating and a detector array.
  • Figure 3 shows conventional spectra of some common disinfectant species.
  • the peaks of HOCI and OCI ' are easily identified in the spectra, showing strong absorption features at about 235nm and 292nm.
  • a monochloramine absorption is also visible in the curves, overlapping the HOCI absorption, but slightly displaced at 254nm.
  • a tap water spectrum is also shown in Fig. 3.
  • the present invention is based on the realisation that what is needed is to determine small changes in spectral shape which are superimposed on large interfering absorption features.
  • two spectra are measured, one for the sample as first obtained and one with the species of interest modified by for example being at least partially removed.
  • One method of removing the chlorine species could be adsorption onto activated carbon but this would not be convenient at low sample flow rates because of the large volume of carbon required and the detrimental affect this has on sampling times.
  • a more effective method is to expose the sample to conditions in which the chlorine species are at least partially removed. This may be achieved by irradiating the sample with light.
  • Fig. 4 shows eight curves representing the spectrum after successive intervals of 5 minutes. However, a very rapid before and after irradiation measurement cycle is desired to reduce drifts in background spectra due to other causes, so a xenon flash-lamp system was investigated.
  • the sample was irradiated in a 10mm path length UV-silica cuvette placed within the reflector of a commercial photographic flash unit. Using a charger, the energy per flash was set at 45 J. The cycle-time was 10 seconds, and five flashes reduced the OCI ' concentration measured by its 292nm absorption peak by 65%. Similar but slightly smaller reductions in the HOCI absorption feature were also measured. Whilst this percentage reduction is not as large as desired, it is adequate for many measurements.
  • Fig. 5 shows the spectral modulation due to a series of xenon flash-lamp flashes for an acidic solution of chlorine (mostly HOCI species present). Alkaline spectra were similar to those of Fig. 4 and are not illustrated.
  • Fig. 6 shows the difference spectra (i.e. differences between subsequent spectra and the original spectrum) for a single concentration at different pH values. The two spectral features at 235nm and 292nm are clearly visible.
  • Fig. 7 also shows the difference spectrum for a tap water sample, showing very little change with irradiation, except below 205nm. Some of the remanent modulation, especially visible as a shift at long wavelengths, is due to a temperature increase after flashing.
  • Fig. 7 shows the differential response in alkaline (predominantly OCI " present) conditions for a series of concentrations from 0.75 ppm to 16 ppm. Real spectral modulation, even in tap and de-ionised water samples, does occur at wavelengths less than 205nm under irradiation.
  • the deuterium lamp used for the UV spectroscopy could also be used for the dechlorination as well as for spectroscopy, particularly using a fixed system with irradiation in situ.
  • the primary limitation of the deuterium lamp is its operating life. Typically, an operating life of 2000 hours at rated drive before a gradual reduction in output to 50% of its initial value is claimed by the manufacturers. Such a short lifetime before replacement of the lamps becomes necessary would represent a disadvantage similar to that of reagent replacement in the prior art. However, lifetime of the lamps appears to be a rapid function of operating current, so it is possible that power management with a low operating power state between measurement phases would extend the life beyond 5000 hours.
  • Medium and high pressure mercury lamps provide a line spectrum of high intensity and could be useful if a suitable wavelength was located.
  • Xenon arc lamps have lower efficiencies but exhibit reduced line structures. Time resolved spectral measurement and simultaneous dechlorination are possible with a xenon flash lamp.
  • Metal halides lamps may also be used but are only available in very high power types. Higher efficiencies could be expected from excimer sources, either as lasers or as incoherent discharge lamps. Many line spectra are available from excimer sources, such as ArF (193nm), KrCI (222nm), KrF (248nm), XeCl (308nm) and XeF (351nm) amongst others.
  • a series of such excimer sources in the form of small-sized lamps may be very useful in performing the method according to the present invention.
  • the investigations described above suggest that rapid dechlorination (and removal of certain other species) using a very intense but short photolytic irradiation from a flash lamp may be the best method of carrying out the invention.
  • the chlorine species could alternatively be removed by continuous irradiation by, e.g. a mercury arc lamp, deuterium lamp or an excimer lamp.
  • the target chemical species may be modified by exposing the sample to conditions other than photolytic degradation.
  • the characteristics of the sample may be modified by passing through it an active species flux generated by a corona discharge.
  • Figs. 8 to 11 illustrate embodiments of the invention which rely upon corona discharge.
  • the illustrated spectroscopic cell is formed from fused quartz and has four planar side walls 1 of equal length and width and a base 2. Three loops 3 of 100 micrometer diameter platinum wire are glued onto the base, the wire being passed out of the cell between the base and one of the side walls.
  • the cell defines an internal space 40mm deep and 10mm wide.
  • the cell was mounted in the optical path of a spectrometer (not shown), the spectrometer used in experiments being a Hewlett-Packard 8452A diode array spectrometer.
  • the optical path of the spectrometer is indicated in Fig. 8 by the arrow 4.
  • the wires 3 are connected to earth through a microammeter 5 as shown in Fig. 8.
  • Samples were introduced to the cell to a depth of 30mm, giving a sample volume of approximately 3ml.
  • a size 5/10 sewing needle 6 was inserted into the open end of the cell and supported such that the vertical position of its point could be adjusted. During experiments the needle position was adjusted such that its point was spaced from the sample meniscus by a fixed amount.
  • the needle was connected by a high voltage cable to the negative terminal of a DC generator (not shown).
  • the generator comprised a 30 kHz transistor and ferrite transformer oscillator generating approximately 1200 volts peak to peak and supplying a multi-stage Cockroft-Walton type voltage multiplier capable of delivering a variable voltage of up to 8 kV.
  • Samples of aqueous chlorine were made up from stock 14% sodium hypochlorite solution, diluted to the ppm concentration level, and adjusted in pH using sodium hydroxide and hydrochloric acid. These were pipetted into the spectrometer cell and the corona electrode was adjusted in height to give a 4mm gap between the needle point and the meniscus.
  • Fig. 10 shows results obtained with a chlorinated water sample repeatedly exposed to a corona wind. Zero absorbance difference corresponds to the reference spectrum taken before initiation of a first corona discharge. The spectrum for each of the 13 subsequent measurements is shown in Fig. 10, the first subsequent measurement being taken 30 seconds after initiation of the first corona discharge but before initiation of the second corona discharge, and the other measurements being taken at 15 second intervals thereafter during intervals between successive discharges.
  • the corona current was flowing, the surface of the meniscus was visibly dented by the corona wind, and caused to move around actively. It is believed that this aids mixing in the confined spectrometer cell.
  • Fig. 10 shows results obtained with a chlorinated water sample repeatedly exposed to a corona wind. Zero absorbance difference corresponds to the reference spectrum taken before initiation of a first corona discharge. The spectrum for each of the 13 subsequent measurements is shown in Fig. 10, the first subsequent measurement being taken 30 seconds after initiation of the first corona discharge but before
  • Determination of the hypochlorite concentration from the results shown in Fig. 10 requires a calibration curve. To obtain this, many samples were prepared and measured using another (reference) analytic technique, that is by using the indicator DPD. It would have been possible to use alternative techniques, for example titration. Each sample was then exposed to the corona wind for a fixed time and at a controlled current level. The current was regulated by directly measuring it as shown in Fig. 8 and by adjusting the voltage to maintain a constant current. Alternatively, the total charge delivered could have been measured by integrating the current over time, and stopping the current when a predetermined total charge was reached.
  • the sample is repeatedly exposed to a corona wind and the absorbance is measured between successive exposures.
  • the change in absorbance is plotted for each wavelength
  • Fig. 11 the absolute absorbance is plotted against wavelength.
  • the uppermost curve in Fig. 11 corresponds to a measurement made before initiation of the corona discharge.
  • the other curves correspond to measurements made after 30 seconds and at 15 second intervals thereafter.
  • corona discharge Only one configuration of corona discharge is described above. This used a negative electrode polarity in an air atmosphere. There may be additional advantages in using a positive electrode polarity, in removing the charged species of the corona wind with a grounded grid electrode, and in operating in atmospheres other than air. The technique is also of interest for non-aqueous samples, for gas samples which have UV absorbing features, and with other forms of detection such as infrared spectroscopy.
  • the method of the invention relies upon the comparison of spectra generated before and after modification of the characteristics of a sample. That comparison may be made using for example the technique of principal component analysis. The application of this technique in the context of the present invention is described below by reference to a worked example.
  • Raw calibration data were generated from nine samples of water, the samples having the following pH values and concentrations of HOCI and OCI ' :
  • T: X.P.(P r .P)
  • Ypred was calculated on the basis of the nine spectra initially used for calibration purposes to produce the following:

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  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)
  • Investigating Or Analysing Materials By The Use Of Chemical Reactions (AREA)

Abstract

Procédé et dispositif de détermination de la concentration d'une espèce chimique cible dans un échantillon. Un premier spectre est produit qui représente l'absorbance de l'échantillon sur une gamme de longueurs d'ondes. On expose ensuite l'échantillon à des conditions qui modifient, dans l'échantillon, la concentration de l'espèce chimique cible, par exemple, en soumettant cet échantillon à un rayonnement U.V. ou à une lumière visible, ce qui a pour effet de dégrader l'espèce chimique cible, ou bien en générant un flux actif de l'espèce à travers l'échantillon en exposant celui-ci à une décharge par effet corona. On mesure ensuite à nouveau l'absorbance de l'échantillon sur la même gamme de longueurs d'ondes, et on analyse les différences entre les deux spectres afin de quantifier la concentration de l'espèce chimique cible dans l'échantillon non modifié.
PCT/GB1995/002862 1994-12-09 1995-12-08 Detection quantitative d'especes chimiques Ceased WO1996018096A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU41209/96A AU4120996A (en) 1994-12-09 1995-12-08 Quantitative detection of chemical species
GB9711721A GB2310717B (en) 1994-12-09 1995-12-08 Quantitative detection of chemical species

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
GBGB9424922.4A GB9424922D0 (en) 1994-12-09 1994-12-09 Quantitive detection of chemical species
GB9424922.4 1994-12-09
GBGB9502683.7A GB9502683D0 (en) 1995-02-11 1995-02-11 Quantative detection of chemical species
GB9502683.7 1995-02-11

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WO1996018096A1 true WO1996018096A1 (fr) 1996-06-13

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GB (1) GB2310717B (fr)
WO (1) WO1996018096A1 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999012017A1 (fr) * 1997-09-04 1999-03-11 Forschungszentrum Karlsruhe Gmbh Procede et dispositif d'identification de principes actifs
EP1304559A1 (fr) * 2001-10-19 2003-04-23 Tecnologie Dinamiche S.A.S. di Rossi Vincenzo & C. Appareil permettant de mesurer la concentration de chlore dans un circuit de dialyse
WO2003106981A1 (fr) * 2002-06-12 2003-12-24 Baxter International Inc. Capteur optique ameliore et procede permettant de mesurer la concentration d'un constituant chimique au moyen de son absorbance optique intrinseque
EP2942614A1 (fr) * 2014-05-08 2015-11-11 B. Braun Avitum AG Dispositif et procédé de commande de dispositif destiné à la détermination de concentration quantitative de substances sélectionnées dans un liquide extraites par filtration d'un corps d'un patient
WO2016046719A1 (fr) 2014-09-23 2016-03-31 Maytronics Ltd. Analyse de fluide de piscine multiparamétrique, procédé et dispositif de régulation
CN108181252A (zh) * 2018-02-09 2018-06-19 广东贝特涞生物科技有限公司 消毒剂检测装置、添加装置及添加方法
US10746653B2 (en) 2011-04-26 2020-08-18 Ecolab Usa Inc. Fluid property determination based on partial least squares analysis

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4023905A (en) * 1975-12-29 1977-05-17 Britton Chance Flash photolysis split beam spectrophotometer
WO1986004673A1 (fr) * 1985-02-08 1986-08-14 Rijksuniversiteit Leiden Procede et spectrometre de mesure des spectres de difference d'absorption de reactions de radicaux
JPS62228145A (ja) * 1986-03-29 1987-10-07 Shimadzu Corp 紫外線式有機物測定装置
US5298428A (en) * 1990-02-12 1994-03-29 United States Department Of Energy Self-referencing spectrophotometric measurements

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4023905A (en) * 1975-12-29 1977-05-17 Britton Chance Flash photolysis split beam spectrophotometer
WO1986004673A1 (fr) * 1985-02-08 1986-08-14 Rijksuniversiteit Leiden Procede et spectrometre de mesure des spectres de difference d'absorption de reactions de radicaux
JPS62228145A (ja) * 1986-03-29 1987-10-07 Shimadzu Corp 紫外線式有機物測定装置
US5298428A (en) * 1990-02-12 1994-03-29 United States Department Of Energy Self-referencing spectrophotometric measurements

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 012, no. 095 (P - 681) 29 March 1988 (1988-03-29) *

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999012017A1 (fr) * 1997-09-04 1999-03-11 Forschungszentrum Karlsruhe Gmbh Procede et dispositif d'identification de principes actifs
US6429015B1 (en) 1997-09-04 2002-08-06 Forschungszentrum Karlsruhe Gmbh Method for identifying active substances
EP1304559A1 (fr) * 2001-10-19 2003-04-23 Tecnologie Dinamiche S.A.S. di Rossi Vincenzo & C. Appareil permettant de mesurer la concentration de chlore dans un circuit de dialyse
WO2003106981A1 (fr) * 2002-06-12 2003-12-24 Baxter International Inc. Capteur optique ameliore et procede permettant de mesurer la concentration d'un constituant chimique au moyen de son absorbance optique intrinseque
US7002670B2 (en) 2002-06-12 2006-02-21 Baxter International Inc. Optical sensor and method for measuring concentration of a chemical constituent using its intrinsic optical absorbance
US10746653B2 (en) 2011-04-26 2020-08-18 Ecolab Usa Inc. Fluid property determination based on partial least squares analysis
DE102014106489A1 (de) * 2014-05-08 2015-11-12 B. Braun Avitum Ag Vorrichtung und Vorrichtungs-Steuerungsverfahren zur quantitativen Konzentrationsbestimmung ausgewählter aus einem Patientenkörper ausgefilterter Substanzen in einer Flüssigkeit
CN105092504A (zh) * 2014-05-08 2015-11-25 B·布莱恩·阿维图姆股份公司 用于定量浓度测定在流体中的从患者身体中滤出的所选物质的设备和设备控制方法
US9423338B2 (en) 2014-05-08 2016-08-23 B. Braun Avitum Ag Apparatus and apparatus control method for the quantitative concentration determination of selected substances filtered out of a patient's body in a fluid
EP2942614A1 (fr) * 2014-05-08 2015-11-11 B. Braun Avitum AG Dispositif et procédé de commande de dispositif destiné à la détermination de concentration quantitative de substances sélectionnées dans un liquide extraites par filtration d'un corps d'un patient
CN105092504B (zh) * 2014-05-08 2020-12-22 B·布莱恩·阿维图姆股份公司 体外体液净化设备和设备控制方法
WO2016046719A1 (fr) 2014-09-23 2016-03-31 Maytronics Ltd. Analyse de fluide de piscine multiparamétrique, procédé et dispositif de régulation
EP3198091A4 (fr) * 2014-09-23 2018-05-23 Maytronics Ltd. Analyse de fluide de piscine multiparamétrique, procédé et dispositif de régulation
US10816528B2 (en) 2014-09-23 2020-10-27 Maytronics Ltd. Multi parameter swimming pool fluid analysis and regulating method and device
CN108181252A (zh) * 2018-02-09 2018-06-19 广东贝特涞生物科技有限公司 消毒剂检测装置、添加装置及添加方法

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Publication number Publication date
GB9711721D0 (en) 1997-08-06
GB2310717A (en) 1997-09-03
AU4120996A (en) 1996-06-26
GB2310717B (en) 1999-04-07

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